Stop mechanism for textile doubling and twisting machines



y 1962 .1. w. B. CLAYTON 3,032,962

STOP MECHANISM FOR TEXTILE DOUBLING AND TWIS'IYING MACHINES Filed NOV. 21, 1960 Imus Mfg g 4fr) 184/6 a/S United States PatentO 3,032,962 STOP MECHANISM FOR TEXTILE DOUBLING AND TWISTIN G MACHINES James William Barnes Clayton, Accrington, England, assignor to.T.M.M. (Research) Limited, Oldham, England Filed Nov. 21, 1960, Ser. No. 70,746 Claims priority, application Great Britain Nov. 24, 1959 4 Claims. (CI. 57-83) The invention is concerned with the delivery roller arrangements employed in textile doubling and twisting machines for withdrawing the yarn from the supply packages and for imparting the degree of tension requisite for the correct performance of the doubling or twisting operation.

The invention is further concerned with the provision in such machines of means for detecting a breakage or reduction in the tension of the yarn or thread delivered by the delivery roller assembly.

In such machines it has hitherto been conventional practice to use a roller assembly including a single bottom roller extending throughout the length of the machine and driven by positive means at the end thereof; in conjunction with such bottom roller there are provided in respect of each spindle one or more short top rollers which are self-weighted and supported in small brackets. For a light twisting operation a single line of top rollers will afford sufficient tension, whereas a heavy twisting operation may necessitate the use of three or more rollers about which the ends of yarn are passed to reduce the possibility of slip of the yarn through the roller nip. It has been customary to use top rollers of considerable size for the sole purpose of obtaining the weight necessary to ensure a positive nip, but this practice is disadvantageous, not only because large heavy rollers are expensive, but also for the reasons that they are inconvenient to handle and, if they should be dislodged from their supports, they may damage other parts of the machine upon which they may fall.

With the object of providing an improved tension roller arrangement by which these disadvantages may be avoided, the present invention proposes (a) that a single top roller shall be supported by a bracket arm which is mounted for pivotal movement about an axis parallel to the bottom roller axis, the said single top roller being arranged to rest upon the surface of the bottom roller along a line so disposed in relation to the position of the bracket pivot axis that there is a wedging action between the two roller surfaces under the weight of the top roller and its said bracket, such wedging action being accentuated by the tension of a yarn drawn between said surfaces and about the surface of the top roller, and (b) in combination with said top roller, automatic means, sensitive to the tension of the yarn, for arresting rotation of the top roller and delivery of the yarn in the event of a breakage between the top roller and the twisting unit.

Such automatic roller-arresting means may comprise a feeler arm mounted upon the top roller support with capability of pivotal movement about an axis parallel to the axis of said roller, said feeler arm being arranged to rest at its free end upon said yarn or thread and to be supported by the tension thereof in a raised position. A locking or detent member carried by the feeler arm is normally held inoperative, but in the event of a breakage of the yarn or thread, or a reduction in the tension thereof, such that the feeler arm is no longer supported and is allowed to drop, said locking or detent member is arranged to engage a part of the roller and by arresting its rotation discontinue further delivery of the yarn or thread.

One manner in which the invention may be carried into "ice eifect is hereinafter described with reference to the accompanying diagrammatic drawings in which FIG. 1 is a partly sectional side elevation of one form of apparatus in accordance with the invention, FIG. 2 is a plan thereof, and FIG. 3 is a fragmentary view similar to FIG. 1 but illustrating a modification.

In the drawings, the reference numeral 10 indicates the continuous bottom feed roller of a doubling or twisting machine, and 11 one of the individual top rollers which co-operates with the roller 10. Said roller 11 is provided with a flange 111. The top roller 11 is carried by an arm 12 which is pivotally mounted on a fixed rod or shaft 13 having its axis parallel to that of the roller 10 and suitably supported on the machine frame. Said arm 12 may be raised, together with the roller 11, to the inoperative position shown in chain-dotted lines in FIG. 1; when so raised a fixed stop 14 engages an abutment 121.

As will be seen, the roller 11 rests upon the surface of the roller 10 along a line such that there is a wedging action between the two roller surfaces under the weight of the roller 10 and the arm 12. Such wedging action is achieved by the location of the axis of the rod or shaft 13, having regard to the length of the arm 12 and the diameters of the two rollers.

In operation, the yarn A is led from the supply package (not shown) to pass partly round the under surface of the roller 10, through the nip of the rollers 10 and 11 and over the roller 11, whence it proceeds through a guide eye 15 carried by a feeler lever 16 which is pivoted on the arm 12 at 161. Secured to said lever 16 is a catch 17, and the arrangement is such that in the event of a breakage in the yarn A between the roller 11 and the twisting unit, so that the lever 16 is no longer supported by the tension of the yarn, the lever 16 is free to pivot by gravity about the point 161 until the catch 17 engages an abutment 18 in the flange 111 of the top roller 11, thus arresting the top roller and, by discontinuing the delivery of the yarn, preventing unnecessary waste.

In the alternative embodiment shown in FIG. 3 the top roller 11' is arrested by the abutment of a peg 19 on the roller with a detent 162 in the lever 16.

What I claim as my invention and desire to secure by Letters Patent is:

1. A textile yarn doubling or twisting machine comprising a roller delivery mechanism incorporating a bottom roller and, in respect of each twisting unit in said machine, an individual top roller, said rollers being adapted for passing textile yarn therebetween, each such top roller being supported by a bracket arm mounted for pivotal movement about an axis parallel to the roller axes and positioned relative to said roller axes so that the top roller rests upon the surface of the companion bottom roller along a line so disposed in relation to the position of the pivot axis of said bracket arm to cause a wedging action between the two roller surfaces, and automatic means, sensitive to the tension in the textile yarn passing from around said top rollers, for arresting rotation of the top roller and due to the wedging action between said top and bottom rollers also arresting delivery of the yarn, in the event of a breakage between the rollers and the twisting unit.

2. A machine as claimed in claim 1, wherein the automatic roller-arresting means comprises a feeler member mounted upon the top roller support with capability of pivotal movement about an axis parallel to the roller axis, said feeler member being arranged to rest at its free end upon the yarn or thread and to be supported by the tension thereof in an elevated position, and a locking or detent member on the feeler arm which ordinarily occupies an inoperative position but, in the event of a breakage or reduction in the tension of the yarn or thread will on falling engage a part of the roller so as to arrest its rotation.

3. A machine as claimed in claim 2, wherein the feeler member carries a terminal guide eye through which the yarn passes on its path after leaving the delivery rollers, so that the feeler member is normally maintained in an elevated position by the yarn or thread tension.

4. A machine as claimed in claim 2, wherein the feeler member carries a catch, and wherein the top roller is References Cited in the file of this patent UNITED STATES PATENTS Sharkie July 23, 1912 FOREIGN PATENTS Great Britain of 1914 

